I will never mash on the stovetop again, temperature control is too unpredictable. I spiked a high temp. at 30 min. that may have ruined me, but this is what I don't understand. I mashed about twice as long as expected, because iodine test continued to be positive. Finally I gave up and sparged, but runnings were negative with the iodine test. Is there an explanation for this? And, if I had poor conversion as I expect, since the temperature may have been above 170, can I increase fermentation later by adding enzymes, without affecting quality too much?

Secondly, this was a small batch (2.5 gallons) for a couple of reasons, and I used leaf hops for flavor and aroma. This absorbed about 20% of my volume, but did not seem to effect actual efficiency. Should I contribute extra water to recipes when I use leaf hops in the future?

Lastly, I needed about a gallon more sparge water than I expected via ProMash (leading to a long boil); I did not suspect channeling, and I sparged over 30 minutes. Is there anything I can do differently here?

It's funny. That which I expected the most difficulty with was easy (sparging). I thought temperatures would be merely tedious, not impossible to maintain. I have a Camp Chef on the way.

This is a follow-up on the correct interpretation of the iodine test. I don't recall the fine details from Jr. High. Should a very weak color change be interpreted as positive, and/or should a gray/black color be interpreted as positive? I just did this experiment in the kitchen with cornstarch (intense deep blue) and wheat sugar syrup (faint gray). It is the faint gray color I was getting in my mash.

The iodine will turn a deep blue-black if starch is present in the mash. It will remain a red/brown mahogany color if the starch has converted. If diluted I suppose you might interpret that as faint gray. If you want to be sure of the difference, keep a tiny portion of the grist behind and mix it with water just before you test your mash for conversion. Then test each of the two samples. You will notice the difference right away. Another tip is to test a few drops of the liquid portion of the mash only. Grain husks and particles often will turn black, causing you to think the mash has not converted when in fact it has.

Thank you for your advice. I found some fugitive grains from today's session and mixed with water and got an obvious blue color, much different from the gray color in the mash earlier today. I may get a good beer out of today's near tragedy, yet.